Unless you’ve been hiding under a rock, you’ll have noticed that beards have come sprouting back into fashion, at least in the UK and US. To psychologists, this phenomenon raises several inter-related questions, such as – are these men just copying each other; what does a beard do to a man’s attractiveness; does it make him look more macho; and given the answers to the previous, should I grow one too? Well, that last question might apply only to male psychologists. Anyhow, here to help you untangle these issues, we present the latest in our world-famous series of special features: the psychology of beards, digested.

Beards make men look more attractive (except when they don’t)
One influential theory is that men’s beards are an adornment, like a peacock’s tail, which make them more attractive, especially to the opposite sex. Yet the research on whether men with beards are more attractive is contradictory.

This paper from 1973 that involved undergrads rating men’s faces found that bearded men were considered better-looking (not to mention more masculine, mature, dominant, self-confident, courageous, liberal, nonconforming, industrious, and older). That was the hairy 70s you say, but this study published this very month in Archives of Sexual Behaviour also found that hundreds of women recruited online consistently rated bearded men, regardless of amount of beard growth, as more sexually attractive than their clean-shaven counterparts.

But male readers, before you bin your razor, consider that another study from 1991, involving undergrads doing the rating, found that clean-shaven men were seen as “younger, more attractive, and more sociable” than the beardies, while another paper out this year found that “there was no main effect of facial hair growth on ratings of attractiveness”.

We may have hit peak beard
Part of the reason for these mixed findings is likely that when beards are in vogue, as they are today, a man with a beard no longer stands out from the crowd. Researchers tested this idea a couple of years ago by presenting participants with either lots of pictures of bearded men, or lots of pictures of clean-shaven men, or a mix, before then having them rate the attractiveness of a bunch more men, bearded and non-bearded.

The revealing finding was that bearded men were seen as relatively more attractive after the researchers had created a clean-shaven background context. This supports the idea that beards boost attractiveness when they help make a man distinctive from his peers. The result also complements historical research showing that hair length, side-burns, and beards tend to follow the same cyclical pattern, increasing in popularity and length until they reach a peak and then subsiding again. All of which prompted the researchers to suggest that in current times we may well be close to reaching “peak beard“.

Bearded men look more macho
A rival evolutionary theory for men’s beards suggests that they aren’t so much about attracting women, but more about frightening other men by helping their owners to look aggressive and dominant. The findings here are more consistent. For example, this cross-cultural study from 2012 found that European women from New Zealand and Polynesian women from Samoa rated bearded men’s faces as older and higher social status (but not more attractive) and they perceived bearded men pulling an aggressive face as more aggressive than clean-shaven men doing the same.

Similarly, this recent study found that men with beards were perceived as more dominant. And another paper that’s consistent with the idea of men using their beards to compete found that moustaches have historically been more common in eras when there are lots of eligible men competing for partners.

What else does a beard do to a man’s image?
Like a middle-aged goatee peppered with grey, the findings here are patchy once more. Bearded hipsters will be pleased to know that this paper from 2014 (ratings by university students again!) found that bearded men were considered more trustworthy. Similarly, another study, from 1990, involved participants looking at ink sketches of job applicants – those with beards were seen as more competent (as well as more attractive). And this study of LinkedIn profile pictures found that bearded men were considered to have more expertise (by the way, the same researchers found that spectacles had the same image-enhancing benefit for women).

Also good news for the bewhiskered, this time away from the context of work, a study from 2013 found that men and women perceived full-bearded men as likely to be better fathers than their clean-shaven and less-bearded counterparts. This could tie-in with our earlier dominant/macho theme – perhaps people assume bearded men will be better fathers because they think they are more masculine and have more status and so will be better protectors and providers.

And yet, just when you thought it was safe to let your facial hair down, this study from New Jersey lands a blow for the razor-loving corner and will surely make beard owners bristle: researchers asked participants to pretend they were jurors on a trial then showed them pictures of two men, one shaven, one bearded. They were asked to say which man they thought was on trial for rape and which was a plaintiff in a head-injury case. Seventy-eight per cent of them chose the bearded guy as the rapist! What’s more, in a follow-up, the researchers asked hundreds more participants to sketch the face of a criminal offender – 82 per cent of their drawings featured a man with a beard.

These criminal-related findings might seem strange at first, especially given the positive connotations of having a beard, such as seeming more competent in a job application. But perhaps it all comes down to the fact that beards make men appear more masculine and dominant and those attributes have different connotations in different contexts. Seeing that your male doctor is bearded might make him seem more experienced and expert, for instance, but seeing that a criminal suspect is bearded might make him seem more aggressive and threatening.

For one more context where beards seem to provoke negative assumptions, consider this study from 2013, which involved participants looking at photos of men who supposedly worked on the front desk at a hotel, and judging how assuring and competent they would likely find him to be in this role. Bearded Caucasian men received poorer ratings than their smooth-chinned counterparts (the same finding did not apply to African-American men), leading the researchers to recommend “Except under special circumstances, hotel firms should not permit their employees to wear beards.”

—And finally, if this research roundup is tempting you to grow a beard, perhaps as a way to feel more manly, you might first consider wearing a fake one, to test out how you like it. A study from 1986 found that male undergrads felt more masculine simply through wearing an appropriately coloured theatrical beard, and more so than they did after wearing a bandana in the style of an outlaw. “… a person tends to form highly detailed and stereotypic impressions of another person on the basis of just a few physical features, with beards being a very strong stimulus characteristic,” the researchers said. “The present study shows that the wearers of those beards follow this societal tendency and stereotype themselves in the same way.”